Dungeons and Dragons
Coin-Sith
The coin-sith are fey hounds, trained and used by the daoine sidhe as companions and watchdogs. Like fairies, they may become invisible to mortals at will, and prefer to be so. When visible, they appear as large, black and green dogs; their eyes sometimes glow with a disturbing, flickering verdance; and their tongues may have a similarly fluctuating green radiance, These unusual characteristics are often described inaccurately as fire, like hellhounds; some do speculate, however, that there is some relation between fairy dogs and those infernal canines.
Like normal dogs, coin-sith are intelligent and fiercely loyal to their masters.
The above information was taken from the Dungeons and Dragon’s Creature Crucible, Tall Tales of the Wee Folk . All of this information here has been copyrighted to TSR Inc and Wizards of the Coast.